Features: Complete set with 9 interchangeable heads size from 2.5mm to 6.5mm 2 Brightness levels---dim or bright suits various lighting conditions. Built-in lithium battery can be recharged and reused It can be used as a small flashlight when it is not installed 15 minute quick charging and long lasting battery 7-9 hours. USB charging can be done by wall adapter , power bank or desktop/laptop computer etc. It comes with a stylish zip case for convenient to storage. Interchangeable heads each marked with hook sizes. Great for long or short projects for crocheters at all levels. Complete Set - Crochet Hook Size: 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm. Specifications: Handle material:ABS+Silicone Crochet Hook material:PC Crochet Hook Sizes: 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mmincludes:9 x Interchangeable heads 1 x USB charging cable 1 x Small wrench 1 x Case